What do you want? maximum capacity or highest terminal voltage over the
life of the battery: most AA alkalines are 2.8 AH and the newer Lithiums
are not much better at around 3.0 AH but keep the terminal voltage at
1.6V to 1.5V for most of the life of the battery.

But are extremely poor value for money unless absolutely necessary for the
application.
IMO the best alkaline batteries are the ones that give the best life Vs cost
ratio, and don't leak. Duracell fails on the first, Eveready fails on both
counts!
I now use Chinese ones exclusively and don't have any problems.

FWIW, I've had Duracells leak on a fairly regular basis and would
never use them again for that reason. But I don't recall ever having
either Energizer or Eveready Gold ones leak.
A few years ago Rockby Electronics was selling 9V "Buzz" alkaline
batteries very cheaply. Every one of them leaked badly. I suppose you
get what you pay for.

I have had so many Eveready's leak I once had a collection for display
purposes!
I once took an *unopened* packet of Eveready Golds that were leaking back to
their office in Melbourne. They were not at all surprised, and offered me
Heavy Duty blacks instead!

It was nearly ten years ago I stopped buying, and I had a sizeable
collection dating for about ten years previous to that.
I haven't bought an Eveready since then, so they may have improved.
(couldn't get any worse that's for sure)
However one thing I am certain of is that I have had *FAR* fewer batteries
leak since I stopped buying Eveready, and I have saved a lot of money buying
batteries for half the price, which last nearly as long.

I just bought a pack of 4*AA alkalines today for $1.99. Try getting
Eveready's for that!
Somebody's got to pay for their marketing expense I guess, as long as it's
not me :-)

I have a 3.3 to 2.7 volt microprocessor data logging project and I'm
interested in hearing about various experiences with batteries, this
project has to run for about a year on two AA in a tropical marine
environment.

If I had my way it would be a Zilog Z8 Encore XP, The selected device
is a MAXQ2000 16 bit RISC design it's fast and low power but programming
in assembly is fun as I don't have the C compiler for it.

I ported the 28pin Z8 temp sensor example to the 8pin Z8 and had it
hooked up to a class one bluetooth transmitter with a new antenna
design: I had over 3 Km before I ran out of space for it. I understand
the current world record is less than that.

Mark was interested in powering a microcontroller circuit under
fairly extreme conditions for a long time, so lithiums seemed to be a
reasonable readily-available choice for that application.
For more mundane uses, quite likely alkalines would be a more
cost-effective choice. :)

Possibly, but without knowing the actual current drain, time between
service, possible power availabilty from other sources, size and weight
constraints etc. etc. it's impossible to say whether it's a *good* option.

I can tell you what brand to stay away from - I bought a pile of Jaycar's
"Eclipse" brand 9V alkalines a month ago and stuffed them into various
different smoke alarms (different brands and models). Within 3 days, every
smoke alarm was beeping saying the battery was flat.

I felt like taking it up with Jaycar, but that sort of thing is hard to
prove, and I can guess the level of Jaycar's care factor.

Do yourself and other consumers a favour and return the batteries for a
refund.
Sometimes faulty stock or a shonky product get marketed, unfortunately not
always
at the vendor's knowledge. I reckon it would be uneconomical and
impractical to
test every item that makes its way to the shelves, so take them back and get
them to
perform a discharge test on their "new" floor stock. It could be that they
have been
supplied with a bad batch of batteries.

Thanks! That chart reflects my experience with Eveready Titanium
cells. A lot of hype and a considerably higher price for a negligible
improvement in performance over normal alkalines, even under heavy
loads.